When the subject of undies is ever discussed (not often) in our family we usually refer to female undergarments etc as Lorne-jerry after having become almost hysterical when I took DD1 to get first bra and the posh assistant kept talking about how important 'well fitting Lornejerry' was for developing bosoms!
Gally and Feetle Pedant alert! Stubbies are an actual Australian brand selling other gear as well as shorts, and when we lived in Hongkong they were very popular with our Australian friends. I'm not sure whether the name was actually used as a generic term, as you imply Feetle www.stubbiesworkwear.com.au/bottoms-shorts.html